1. Field of the Invention
This invention relates to a recoil starter for starting a small-size engine and, in particular, to such recoil starter which is capable of surely engaging a dog with a crank pulley, of easing the strength required for these components, and of surely preventing a rope from getting out of place.
2. Description of the Prior Art
A recoil starter frequently used for starting a small-size engine, in general, includes a starter case, a reel supported rotatably within the starter case and having a rope groove formed in the peripheral surface thereof in which a rope can be wound, a dog mounted to be rotatable simultaneously with the reel and, when the reel is acceleration rotated, projectable externally in the radial direction to come into engagement with a crank pulley connected with the engine to thereby rotate the pulley, a recoil spring for energizing the reel in the winding direction thereof, and a handle disposed at a pulling side end portion of the rope.
Such recoil starter includes an engaging means for engaging the dog with the crank pulley. As the engaging means, there are conventionally known two types of devices: one of them is a device which engages the dog with an open window formed in the crank pulley, as disclosed in Japanese Utility Model Publication (Jikkai) No. 54-106433; and the other is a device which engages the dog with a convex-shaped step portion formed in the inner peripheral surface of the crank pulley, as disclosed in Japanese Utility Model Publication (Jikkai) No. 56-17370.
With these conventional engaging devices, the dog can be surely engaged with the crank pulley. However, for example, in the case of the former device, since a torsional force and the like is applied to the dog and a reel which supports the dog, the components concerned must be increased in strength. For instance, the dog must be constructed to be thick and also the surface of the dog must be hardened, or the reel must be constructed to be thick and also the crank pully must be quenched.
Also, in the case of the latter device, although the components concerned do not require such great strength as in the former engaging device, the hardening treatment of the dog surface and the above-mentioned thermal treatment of the crack pulley are still required. Further, in engaging the dog with the crank pulley, the dog may slide along on the inner peripheral surface of the crank pulley, resulting in poor engagement.
On the other hand, there is the possibility that the rope of the recoil starter may slip off from the rope groove according to the timing for pulling back the rope into the rope groove in the reel after the starting operation.
For these reasons, conventionally, for example, as disclosed in Japanese Utility Model (Jikkai) No. 61-76167, a substantially dish-shaped rope cover is mounted by spot welding to the inside of the starter case and the peripheral wall thereof is disposed adjacent to the outside of the rope groove so as to prevent the occurrence of the above-mentioned problems.
However, in the last-mentioned conventional rope cover, due to the fact that a notch must be formed in the rope pull-out portion thereof, there arises another possibility that the rope may slip off in the rope pull-out portion. Also, the mounting of the rope cover requires spot welding as well as forming and machining, which takes much time and labor. Further, the yield of the material used is poor and the productivity of the rope cover is low.